FLAWED BEHAVIOUR:
Copy and paste only works between 2 active applications. This is very limiting!
If you are in the single task oriented MiniMenu you have no chance at all to share the clipboard between apps!
If you are in the multi tasking oriented XFCE desktop environment you can only share between apps running in parallel! Not with apps which started after the source app has been terminated.
DESIRED BEHAVIOUR:
The clipboard content (within reasonable limits of course) should remain, regardless of the source application, so that you can paste at any later moment into any application.

That annoying bug still exists in SuperZaxxon Final, and troubles the multi tasking experience a lot.
Sometimes one would like to copy text from a buggy/crash-likely app before further editing/submitting, and paste it into another app/file as a backup.
Sadly the rudimentary computing feature of "copy/paste between apps of one OS" does not work.